The assignee of the present invention currently is manufacturing and selling two, raster scan, colour projectors. One is a video/data/graphics projector accommodating horizontal frequency scanning rates from 15 KHz (television) to 32 KHz. The other is a CAD/CAM projector that scans horizontally from 32 KHz to 71 KHz. Prior to the present invention, it was not possible to provide a single projector that would accommodate the total range from 15 KHz to 71 KHz while maintaining ease of customer operation.